BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The invention relates to a carrier and a method of manufacturing the carrier and,
more particularly, to a carrier for rotatably supporting rotating bodies such as gears
and pulleys and a method of manufacturing the carrier.
2.Description of Related Art
[0002] A planetary gear unit is generally employed in an automatic transmission of an automobile.
The planetary gear unit has a sun gear, a ring gear disposed around the sun gear,
a planetary gear or a pinion (hereinafter referred to generically as a planetary gear)
disposed between the sun gear and the ring gear so as to engage them, and a carrier
for rotatably supporting the planetary gear.
[0003] As an example of a carrier for supporting a planetary gear or the like of a planetary
gear unit, Japanese Patent Application Laid-Open No. HEI 10-288248 discloses a planetary
gear unit for an automatic transmission according to the related art of the invention.
This planetary gear unit has a ring gear, a sun gear and a pinion that engage one
another, and a carrier for rotatably supporting the pinion. The carrier is composed
of a boss connected to a shaft of the automatic transmission, a radially extended
plate, a carrier plate formed of a salient axially protruding from the radially extended
plate, and a base plate having holes into which the salient of the carrier plate is
fitted. The salient of the carrier plate is made thicker than the boss and the radially
extended plate by differential-thickness press working.
[0004] In the planetary gear unit disclosed in the aforementioned publication, as shown
in Fig. 39, a carrier C' is composed of a carrier plate 31 spline-connected to a shaft
of an automatic transmission and a disc-shaped base plate 32. The carrier plate 31
is composed of a disc-shaped plate 31a and a plurality of columns (salients) 33 protruding
towards the base plate 32 from the outer periphery of the plate 31a in a direction
substantially parallel to the shaft. Fitting portions 33a with a reduced thickness
are formed at the ends of the columns 33. The base plate 32 is constructed of an annular
sheet material having at its center a through-hole 32a through which a shaft (not
shown) or a sun gear (not shown) is inserted. Fitting holes 32b, into which the fitting
portions 33a formed at the ends of the columns 33 of the carrier plate 31 are fitted,
are formed on the outer circumferential side of the base plate 32. The carrier plate
31 and the base plate 32 are connected by fitting the fitting portions 33a formed
at the ends of the columns 33 into the fitting holes 32b and welding parts of the
fitting portions 33a fitted into the fitting holes 32b to the base plate 32. That
is, according to this carrier, the carrier plate 31 and the base plate 32 are formed
individually, assembled, welded, and then integrated. The carrier plate 31 and the
base plate 32 are obtained from press-worked sheet materials. The aforementioned publication
also discloses that the carrier plate and the base plate can be formed by forging
or forging + cutting and the like instead of press working. In such a carrier, the
pinion is inserted into the carrier among the columns 33 and between the carrier plate
31 and the base plate 32, and openings 35 defining a space for engagement of tooth
tops of the pinion gear with the ring gear are made.
[0005] According to another related art, the base plate 32 and the carrier plate 31 having
the columns 33 as in the carrier of the aforementioned related art are formed by sintering,
assembled, connected by waxing instead of welding, and then integrated into a carrier.
[0006] In addition, according to still another related art, the carrier plate 31, the base
plate 32 and the columns 33 are cast and integrated into a carrier. In this related
art, in order to ensure that opposed faces of the carrier plate 31 and the base plate
32 are parallel to each other, the carrier plate 31 and the base plate 32 are cut
after the carrier has been formed integrally.
[0007] However, among the aforementioned related arts, as for the carrier disclosed in Japanese
Patent Application Laid-Open No. HEI 10-288248, as described above, every time a carrier
is manufactured, the carrier plate 31 and the base plate 32 that have been formed
individually need to be assembled, connected by welding or waxing, and then integrated.
For this reason, the number of manufacturing processes is great and each process requires
its own plant, which causes a problem of the inability to reduce the cost.
[0008] Furthermore, for the purpose of rotatably supporting rotating bodies, the carrier
is required to guarantee a high degree of parallel precision of the opposed faces
of the carrier plate 31 and the base plate 32. However, among the aforementioned related
arts, as for the art wherein the carrier plate 31 and the base plate 32 that have
been formed individually by press working or sintering are assembled by welding or
waxing, the parallel precision of the opposed faces cannot be enhanced due to an error
caused during an assembling operation, a tolerance of pressing during the manufacture
of the carrier plate 31 and the base plate 32, a distortion caused during sintering,
welding heat at the time of connection, or a distortion caused by waxing. In order
to solve this problem, it can be considered to dispose a mandrel having a predetermined
width between the opposed faces of the carrier plate 31 and the base plate 32 after
the carrier plate 31 and the base plate 32 have been integrated, and swage them towards
the mandrel. However, in the aforementioned related art, since a welded portion or
a waxed portion for connecting the carrier plate 31 and the base plate 32 cracks,
it is impossible to perform swaging.
[0009] Further, among the aforementioned related arts, in the case where the carrier plate
31 and the base plate 32 that have been formed individually are assembled by welding,
since it is necessary to prevent the fitting portions 33a of the columns 33 and the
base plate 32 having the fitting holes 32b from being melted down during welding and
guarantee sufficient rigidity, it is impossible to thin at least the base plate 32
and the columns 33 or narrow the peripheries of the columns 33. This makes it impossible
to save the weight of the carrier.
[0010] In addition, in the case where the columns 33 of the carrier plate 31 and the base
plate 32, which have been pressed, are assembled by welding, since the carrier plate
31 and the base plate 32 have been formed individually, the interrupted flow of a
material causes a problem of low rigidity. In the case where the columns 33 of the
carrier plate 31 and the base plate 32, which have been formed by sintering, are assembled
by welding, since powder materials with a low density are used and there is no material
flow, there is caused a problem of much lower rigidity.
[0011] Among the aforementioned related arts, as for the carrier into which the carrier
plate, the base plate and the joints are cast and integrated, it is necessary to cut
the carrier plate and the base plate after the carrier has been formed integrally.
For this reason, the number of manufacturing processes increases and materials are
wasted, which causes a problem of an increase of the cost. Because the carrier that
has been formed by casting is obtained simply by forming a molten material and a density
of contents of the carrier is low and there is no material flow, there is caused a
problem of even lower rigidity.
[0012] Because of the problem of low rigidity as described above, namely, the problem of
low rigidity per unit weight, the carrier that has been manufactured by sintering
or forging needs to be made thick so as to guarantee predetermined rigidity. This
causes problems of more wasted materials and the inability to save the weight of the
carrier.
SUMMARY OF THE INVENTION
[0013] The invention has been made in consideration of the aforementioned problems. It is
an object of the invention to provide a carrier having a construction capable of enhancing
parallel precision of opposed faces with a reduced number of processes and saving
the weight through increased rigidity. It is also an object of the invention to provide
a carrier having a construction that makes its manufacture easy.
[0014] Furthermore, with a view to solving the aforementioned problems, it is also an object
of the invention to provide a method of manufacturing a carrier wherein the number
of manufacturing processes can be reduced with a simple structure, wherein the parallel
precision of opposed faces can be enhanced easily, and wherein the weight can be saved
through increased rigidity.
[0015] In order to achieve the aforementioned objects, there is provided a carrier according
to a first aspect of the invention wherein a pair of flanges opposed to each other
and designed to rotatably support rotating bodies therebetween and joints for connecting
the flanges are integrally formed through plastic deformation of a single material.
[0016] In the carrier according to the first aspect of the invention, the flanges and the
joints are integrally formed through plastic deformation of a single material with
uninterrupted flow of the material. Therefore, the number of parts is reduced and
the processes of assembling and bonding become unnecessary so that the carrier is
formed with a reduced number of processes. Thus, the parallel precision of the opposed
faces is enhanced at a low cost, and the weight can be saved through high rigidity.
[0017] The joints may be disposed along outer peripheries of the flanges.
[0018] Because the joints are disposed along the outer peripheries of the flanges, there
is provided a carrier suited to support, as rotating bodies that are rotatably supported,
planetary gears engaging sun gears in an automatic transmission. In this case, a plurality
of joints are disposed along the circumference of the flanges discontinuously, and
openings are made among the joints. Holes through which shafts for supporting the
sun gears are inserted are formed at the centers of the flanges.
[0019] Furthermore, a groove may be formed on a border between the flanges and the joints.
[0020] If the groove is formed on the border between the flanges and the joints especially
on the side of the inner surface of the carrier, the process of bending is guided
by the groove and the border between the flanges and the joints is formed with high
precision. Therefore, an integral-type carrier having a construction that makes its
manufacture easy is provided.
[0021] In a method of manufacturing a carrier according to another aspect of the invention,
a material is formed into the shape of a cup having an opening, and the opening of
the cup is closed off so that a pair of flanges opposed to each other and designed
to rotatably support rotating bodies therebetween and joints for connecting the flanges
are integrally formed.
[0022] According to this aspect of the invention, after the material has been formed into
the shape of a cup, the material is closed off so that the end faces of the opening
in the cup are shrunk radially inwardly. Thereby it becomes easy to manufacture a
carrier having a pair of flanges opposed to each other and designed to rotatably support
rotating bodies therebetween and joints for connecting the flanges. Besides, since
the flanges and the joints are integrally formed from a single material with uninterrupted
flow of the material, the number of parts is reduced and the processes of assembling
and bonding become unnecessary so that the carrier is formed with a reduced number
of processes. Thus, there is provided a method of manufacturing a carrier wherein
the parallel precision of opposed faces can be enhanced at a low cost and wherein
the weight can be saved through high rigidity. A bottom of the material formed into
the shape of the cup is turned into one of the flanges. Peripheral walls adjacent
to the bottom are turned into the joints. An opening-side portion of the cup-shaped
material, which is to be closed off, is turned into the other flange. Thus, according
to the invention, a carrier of a configuration wherein joints are integrated with
the outer peripheries of flanges is manufactured.
[0023] The material is selected from a plate material, a rod material and a tubular material.
[0024] By selecting one of a plate material, a rod material and a tubular material, a method
of manufacturing a carrier easily is provided in a more concrete form. In the case
where a plate material is used, the material can be formed into the shape of a cup
by being bent and/or drawn. In the case where a tubular material is used, the material
can be formed into the shape of a cup by shrinking one end of the material. In the
case where a rod material is used, the material can be formed into the shape of a
cup by being extruded.
[0025] In a method of manufacturing a carrier according to another aspect of the invention,
both end openings of a tubular material are closed off, whereby a pair of flanges
opposed to each other and designed to rotatably support rotating bodies therebetween
and joints for connecting the flanges are formed integrally.
[0026] According to this aspect of the invention, both end faces of openings of a tubular
material are simultaneously closed off so that they are shrunk radially inwardly.
Thereby a carrier having a pair of flanges opposed to each other and designed to rotatably
support rotating bodies therebetween and joints for connecting the flanges is manufactured
easily. Besides, since the flanges and the joints are integrally formed from a single
material with uninterrupted flow of the material, the number of parts is reduced and
the processes of assembling and bonding become unnecessary so that the carrier can
be formed with a reduced number of processes. Thus, there is provided a method of
manufacturing a carrier wherein the parallel precision of opposed faces can be enhanced
at a low cost and wherein the weight can be saved through high rigidity. Axial centers
of a side wall of the tubular material are turned into the joints of the carrier,
and both axial ends of the side wall of the tubular material, which are to be closed
off, are turned into a pair of flanges. Thus, according to the invention, a carrier
having a configuration wherein joints are integrated with the outer peripheries of
flanges is manufactured.
[0027] A bending guide such as a groove may be formed on a border between pre-joints and
the other pre-flange before the material is closed off.
[0028] By forming the bending guide, the process of bending is guided by the guide precisely
when the material is closed off. Therefore, the parallel precision and the dimensional
precision of the opposed faces of the flanges are further enhanced.
[0029] Openings may be made in pre-joints of the material before the material is closed
off.
[0030] If the openings are made, the outer peripheral faces of the flanges are curved towards
the inside of the openings when the material is closed off. That is, the openings
are made in the joints without affecting the parallel precision of the opposed faces
of the flanges. Therefore the parallel precision of the opposed faces is further enhanced.
In the case where a plate material is used, the openings are made by forming the contour
of the material and trimming it at the same time. Thus, the number of processes can
be further reduced.
[0031] In addition, mandrels may be inserted from the openings made in the pre-joints of
the material so as to close off the material.
[0032] The material is closed off with the mandrels inserted into the pre-joints of the
material from the openings that have been made, whereby it becomes possible to close
off the material from its precise position and further enhance the parallel precision
and the dimensional precision of the opposed faces of the flanges.
[0033] Engagement holes for engagement with rotational shafts for rotatably supporting rotating
bodies in the carrier may be made in pre-flanges before the material is closed off.
[0034] If the engagement holes are made in advance in the pre-flanges of the material, the
parallel precision of the opposed faces of the flanges is not affected by the pressing
force or the like generated at the time when the engagement holes are made. Thus,
the parallel precision of the opposed faces is further enhanced. In addition, if a
plate material is used, the engagement holes are made by forming the contour of the
material and trimming it at the same time. Thus, the number of processes can be further
reduced.
[0035] In a method of manufacturing a carrier according to still another aspect of the invention,
a wall surface at the axial center of the tubular material is bulged radially outwardly
so that a pair of flanges opposed to each other and designed to rotatably support
rotating bodies therebetween and joints for connecting the flanges are integrally
formed.
[0036] According to this aspect of the invention, the center of a tubular material is bulged,
whereby a carrier having a pair of flanges opposed to each other and rotatably supporting
rotating bodies therebetween and joints for connecting the flanges is manufactured
easily. Besides, since the flanges and the joints are integrally formed from a single
material with uninterrupted flow of the material, the number of parts is reduced and
the processes of assembling and bonding become unnecessary so that the carrier can
be formed with a reduced number of processes. Thus, the parallel precision of the
opposed faces can be enhanced at a low cost, and the weight can be saved through high
rigidity. Bulged axial centers of the tubular material are turned into the joints
of the carrier, and both axial ends of the tubular material are turned into a pair
of flanges. Thus, according to this aspect of the invention, a carrier having a configuration
wherein joints are integrated with the outer peripheries of the flanges is manufactured.
[0037] Openings may be made in pre-joints of the material before the material is bulged.
[0038] If the openings are made in the pre-joints at the centers of the tubular material
before the tubular material is bulged, the outer peripheral end faces of the flanges
are curved towards the inside of the openings when the material is bulged. That is,
the openings are made in the joints without affecting the parallel precision of the
opposed faces of the flanges. Thus, the parallel precision of the opposed faces can
be further enhanced.
[0039] Engagement holes for engagement with rotational shafts for rotatably supporting rotating
bodies in the carrier are made in pre-flanges before the material is bulged.
[0040] If the engagement holes are made in advance in the pre-flanges of the material, the
parallel precision of the opposed faces of the flanges is not affected by the pressing
force or the like generated at the time when the engagement holes are made. Thus,
the parallel precision of the opposed faces can be further enhanced.
[0041] Furthermore, mandrels may be interposed in positions for mounting rotating bodies
between the flanges so that the flanges are swaged towards the mandrels.
[0042] If the process of swaging is performed with the mandrels interposed in the positions
for mounting rotating bodies between the flanges, there is provided a method of manufacturing
a carrier wherein the parallel precision and the dimensional precision of opposed
faces at positions for mounting rotating bodies between flanges can be further enhanced.
In the case where openings are made in advance in portions of a material, which are
turned into joints in one of the following processes, before the material is formed
in a predetermined manner, mandrels can be inserted from the openings easily.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] Fig. 1 is a plan view of a carrier according to one embodiment of the invention.
[0044] Fig. 2 is a cross-sectional view taken along a line II-II shown in Fig. 1.
[0045] Fig. 3 is a cross-sectional view of a carrier according to another embodiment of
the invention.
[0046] Fig. 4 is a cross-sectional view of a carrier according to still another embodiment
of the invention.
[0047] Fig. 5 is a plan view of a plate material for explaining a method of manufacturing
a carrier according to the invention.
[0048] Fig. 6 is a cross-sectional view taken along a line VI-VI shown in Fig. 5.
[0049] Fig. 7 is a plan view of a state where a pilot hole and engagement holes are made
in one pre-flange of the plate material shown in Fig. 5 and where auxiliary openings
and reference holes are made in pre-joints of the plate material shown in Fig. 5.
[0050] Fig. 8 is a cross-sectional view taken along a line VIII-VIII shown in Fig. 7.
[0051] Fig. 9 is a plan view of a state where the engagement holes in the plate material
shown in Fig. 7 are chamfered.
[0052] Fig. 10 is a cross-sectional view taken along a line X-X shown in Fig. 9.
[0053] Fig. 11 is a plan view of a state where the pilot holes in the plate material shown
in Fig. 9 are formed into through-holes and where the engagement holes in the plate
material shown in Fig. 9 are finished to a dimension allowing engagement with rotational
shafts of rotating bodies.
[0054] Fig. 12 is a cross-sectional view taken along a line XII-XII shown in Fig. 11.
[0055] Fig. 13 is a plan view of a cup-shaped material that has been formed by bending and
drawing the plate material shown in Fig. 11.
[0056] Fig. 14 is a cross-sectional view taken along a line XIV-XIV shown in Fig. 13.
[0057] Fig. 15 is a plan view of a state where a groove designed as a bending guide is formed
on the border between pre-joints and the other pre-flange on the inner periphery of
a wall of the cup-shaped material shown in Fig. 13.
[0058] Fig. 16 is a cross-sectional view taken along a line XVI-XVI shown in Fig. 15.
[0059] Fig. 17 is a plan view of a state where front-end openings in the wall of the cup-shaped
material shown in Fig. 15 are preliminarily closed off at an appropriate angle from
the groove so that the front-end openings are slightly shrunk radially inwardly.
[0060] Fig. 18 is a cross-sectional view taken along a line XVIII-XVIII shown in Fig. 17.
[0061] Fig. 19 is a plan view of a state where mandrels are inserted through the openings
preliminarily closed off as shown in Fig. 17 so that the front-end openings in the
wall are shrunk radially inwardly.
[0062] Fig. 20 is a cross-sectional view taken along a line IIX-IIX shown in Fig. 19.
[0063] Fig. 21 is a plan view of a state where engagement holes are made in the other flange
of the material shown in Fig. 19.
[0064] Fig. 22 is a cross-sectional view taken along a line IIXII-IIXII shown in Fig. 21.
[0065] Fig. 23 is a plan view of a state where the engagement holes shown in Fig. 21 are
chamfered.
[0066] Fig. 24 is a cross-sectional view which is taken along a line IIXIV-IIXIV shown in
Fig. 23 and which also shows a chamfering machine according to one embodiment of the
invention.
[0067] Fig. 25 is a plan view of a state where the engagement holes chamfered as shown in
Fig. 23 are finished to a dimension allowing engagement with rotational shafts of
rotating bodies.
[0068] Fig. 26 is a cross-sectional view taken along a line IIXVI-IIXVI shown in Fig. 25.
[0069] Fig. 27 is a plan view of a state where mandrels are inserted from openings made
in the joints of the carrier shown in Fig. 25 through positions for mounting rotating
bodies between both the flanges and where both the flanges are swaged towards the
mandrels.
[0070] Fig. 28 is a cross-sectional view taken along a line IIXVIII-IIXVIII shown in Fig.
27.
[0071] Fig. 29 is a cross-sectional view of a pressing machine according to one embodiment
of the invention in a state where the preliminarily closed-off material is being closed
off.
[0072] Fig. 30 is a cross-sectional view of a pressing machine according to one embodiment
of the invention in a state where the material shown in Fig. 29 has been closed off.
[0073] Fig. 31 is a cross-sectional view of a method of manufacturing a carrier according
to a second embodiment of the invention.
[0074] Fig. 32 is a cross-sectional view of a method of manufacturing a carrier according
to a third embodiment of the invention.
[0075] Fig. 33 is a cross-sectional view of a method of manufacturing a carrier according
to a fourth embodiment of the invention.
[0076] Fig. 34 is a cross-sectional view of a method of manufacturing a carrier according
to a fifth embodiment of the invention.
[0077] Fig. 35 is a cross-sectional view of a method of manufacturing a carrier according
to a sixth embodiment of the invention.
[0078] Fig. 36 is a cross-sectional view of a method of manufacturing a carrier according
to a seventh embodiment of the invention.
[0079] Fig. 37 is a cross-sectional view of a method of manufacturing a carrier according
to an eighth embodiment of the invention.
[0080] Fig. 38 is a cross-sectional view of a method of manufacturing a carrier according
to a ninth embodiment of the invention.
[0081] Fig. 39 is a cross-sectional view of a carrier according to the related art.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0082] First of all, a carrier according to one embodiment of the invention will be described
in detail with reference to Figs. 1, 2, which show a carrier C for rotatably supporting
planetary gears (not shown) as rotating bodies in a planetary gear unit of an automatic
transmission employed in an automobile and the like as described above. In the following
description, like reference numerals denote like or similar components.
[0083] The carrier C of the invention is integrally formed of a pair of flanges 1, 2 and
a plurality of joints 3 through plastic deformation of a single material. The flanges
1, 2 are opposed to each other and rotatably support rotating bodies therebetween.
The joints 3 connect both the flanges 1, 2. A groove 4 is formed on the border between
the flanges 1, 2 and the joints 3. The carrier C has openings 5 for exposing planetary
gears so that the planetary gears and the like are inserted into the carrier C among
the joints 3 and that the planetary gears can engage ring gears (not shown). Engagement
holes 6, 7 for rotatably supporting rotational shafts of rotating bodies are made
in the flanges 1, 2 of the carrier C respectively.
[0084] Each of the flanges 1, 2, which constitute a pair, is formed generally in the shape
of a disc. In this embodiment, through-holes la, 2a, through which shafts (not shown)
and sun gears (not shown) are inserted, are made at the centers of the flanges 1,
2 respectively. The flanges 1, 2 of the invention function substantially in the same
manner as the carrier plate 31 and the base plate 32 of the carrier C' of the aforementioned
related art. A plurality of joints 3 are formed along outer peripheral edges of the
flanges 1, 2 in the direction parallel to an axis J-J so as to retain opposed faces
of the flanges 1, 2 at a predetermined distance. The joints 3 of the invention function
substantially in the same manner as a plurality of columns 33 protruding towards the
base plate 32 substantially in the direction parallel to the shafts from the outer
periphery of the plate portion 3a of the carrier plate 31 of the carrier C' of the
aforementioned related arts.
[0085] In the embodiment shown in Fig. 1, the flanges 1, 2 respectively have the three engagement
holes 6, 7 for engagement with rotational shafts (not shown) for rotatably supporting
planetary gears. Thus, in this embodiment, the three joints 3 are disposed along the
outer peripheral edges of the flanges 1, 2 substantially at the centers with respect
to the circumferential direction of the engagement holes 6, 7. In addition, reference
holes 8 used as a positioning reference or the like are made in the joints 3 of the
carrier C of this embodiment substantially at the centers with respect to the axial
direction and the circumferential direction of the joints 3.
[0086] The carrier C having such a structure can be formed through plastic deformation of
a single material, for example, by spinning or drawing a plate material W using a
tool such as a spatula or a press roller. Because the thus-formed carrier C is integrally
formed of the flanges 1, 2 and the joints 3 with uninterrupted flow of a material,
it is possible to reduce the number of parts and form the carrier C with a reduced
number of processes, namely, without the necessity of performing assembling and bonding
processes. Furthermore, the parallel precision of the opposed faces of the flanges
1, 2 can be enhanced at a low cost. Because the carrier demonstrates high rigidity,
it is possible to reduce the thickness of the carrier and thus realize a structure
allowing the weight saving of the carrier. As will be described later, if the carrier
C is formed from the plate material W by drawing, the groove 4 is preliminarily formed
in a portion which is to be the inside of the carrier and which is to be a border
between the joints 3 and at least one of the flanges 1, 2 of the material W either
along the entire circumference or discontinuously. Thereby, when the material W is
closed off, it is urged to be bent along the groove 4. Therefore, the border between
at least one of the flanges 1, 2 and the joints 3 is bent precisely. Accordingly,
the parallel precision of the opposed faces of the flanges 1, 2 is further enhanced.
[0087] The carrier C according to the invention is not limited to this embodiment. For example,
in the case of the carrier C employed in the planetary gear unit or the like of the
automatic transmission of the automobile as mentioned above, it is possible to integrally
form a boss 9 so that it continues from the through-hole la or 2a formed at the center
of at least one of the flanges 1, 2 as shown in Fig. 3 in case of necessity, and form
a spline or a gear 10 in the integrally formed boss 9 as shown in Fig. 4. The carrier
C of the invention is not necessarily employed in a planetary gear unit of an automatic
transmission for an automobile or the like. That is, the carrier C according to the
invention is applicable to other purposes.
[0088] The thus-constructed carrier C of the invention eliminates the necessity to assemble
the columns 33 of the carrier plate 31 with the base plate 32 as is the case with
the carrier C' of the related arts (see Fig. 39). Thus, the parallel precision is
not adversely affected by the forming tolerance or the assembling error of the carrier
plate 31 and the base plate 32. The opposed faces of the flanges 1, 2 are formed with
a high degree of parallel precision.
[0089] Next, a method of manufacturing the carrier C according to one embodiment of the
invention will be described in detail with reference to Figs. 5 through 28, which
show a case where the carrier C constructed as described above is manufactured.
[0090] In the method of manufacturing the carrier C according to the invention, the carrier
C having the flanges 1, 2 and rotatably supporting rotating bodies such as planetary
gears between the flanges 1, 2 is manufactured. In this embodiment, the plate material
W is bent and drawn into the shape of a cup, whereby the flange 1 is formed substantially
at the center of the plate material W and a wall 11 (e.g. see Fig. 14) is formed on
the outer periphery of the flange 1. A front-end opening in the wall 11 formed of
an outer peripheral end face Wa of the material W is closed off, and the joints 3
and the flange 2 are integrally formed so that they continue from the flange 1. When
the front-end opening of the material W formed into the shape of a cup or a tube (described
later) is "closed off", it is formed so as to be shrunk radially inwardly.
[0091] Furthermore, in the method of manufacturing the carrier C according to the invention,
among a series of the aforementioned processes, auxiliary openings 5' (e.g. see Fig.
11) or the openings 5 through which rotating bodies or the like can be inserted into
the carrier C are made in pre-joints (3) of the plate material W before the plate
material W is bent and drawn into the shape of a cup, and the engagement holes 6 for
engagement with rotational shafts for rotatably supporting planetary gears designed
as rotating bodies in the carrier C are made in at least one of pre-flanges (1). Further,
the bending guide 4 is formed on the border between the joints 3 and at least one
of the pre-flanges (1), (2) (e.g. see Fig. 16) before the material W is closed off,
and closing-off mandrels 12 are inserted from the openings 5 made in the pre-joints
(3) of the material W that has been bent and drawn into the shape of a cup (e.g. see
Fig. 19). The outer peripheral end face Wa of the cup-shaped material W is closed
off so as to be shrunk radially inwardly. Furthermore, swaging mandrels 13 are inserted
into mounting positions of the rotating bodies between the flanges 1, 2 from the openings
5 made in the joints 3 of the closed-off carrier C (e.g. see Fig. 27), and the flanges
1, 2 are swaged towards the swaging mandrels 13.
[0092] Hereinafter, a series of manufacturing processes according to this embodiment of
the invention will be described in detail. The plate material W of this embodiment
is generally formed into the shape of a disc having a predetermined thickness as shown
in Figs. 5, 6. As indicated by chain lines in Fig. 5, the central portion of the plate
material W corresponds to the pre-flange (1), and the outer peripheral edge of the
plate material W corresponds to the pre-flange (2). An annular portion located between
the central portion (1) and the outer peripheral edge (2) in the radial direction
corresponds to the pre-joints (3).
[0093] As shown in Figs. 7, 8, a generally triangular pilot hole la' is made at the center
of the pre-flange (1) of the thus-formed plate material W, and three auxiliary holes
6', which are to be the engagement holes 6, are made around the pilot hole la'. For
a later-described reason, the auxiliary holes 6' are set in a dimension slightly smaller
than a dimension allowing engagement with the rotational shafts of the planetary gears.
The three auxiliary openings 5' are made in the pre-joints (3) radially outwardly
so as to correspond to the auxiliary holes 6'. The three reference holes 8 are made
at the centers in the circumferential direction of the auxiliary openings 5' and slightly
radially outwardly of the auxiliary openings 5'. The radial dimension of the auxiliary
openings 5' is set to almost half of the width of the joints 3 (the distance between
the flanges of the carrier). Then, more processes are performed to form the openings
5 through which planetary gears or the like can be inserted into the carrier C thus
manufactured.
[0094] Then, as shown in Figs. 9, 10, after the auxiliary holes 6' have been made, the plate
material W is chamfered by press working, cutting operations or the like so that the
peripheries of sides of the auxiliary holes 6' which are to be the inside of the carrier
C are inclined with a diameter gradually increasing towards the inside of the carrier
C. The dimension of the auxiliary holes 6' made in advance changes because of the
chamfering. The chamfering means that the side of the auxiliary holes 6' which is
to be the inside of the carrier C is scraped off.
[0095] Then, as shown in Figs. 11, 12, the plate material W is punched so that the periphery
of the pilot hole la' assumes a generally circular shape, and one of the through-holes
la through which shafts (not shown) and sun gears (not shown) are inserted is made.
A notch 14 as a mark is made in the circular through-hole la for example for the purpose
of detecting the rotational phase of the formed carrier C in the circumferential direction.
The chamfered auxiliary holes 6' are finished into the engagement holes 6 having a
dimension allowing engagement with the rotational shafts of the planetary gears.
[0096] Then, as shown in Figs. 13, 14, the plate material W is bent and drawn into the shape
of a cup by means of pressing or the like, and the flange 1 and the wall 11 extending
substantially perpendicularly to the outer periphery of the flange 1 are formed. By
being closed off in one of the following processes, the wall 11 constitutes the joints
3 and the other flange 2. The auxiliary openings 5' made in advance have almost half
of the height of the pre-joints (3) extending from the outer peripheral edge of the
flange 1 to the wall 11.
[0097] Then, as shown in Figs. 15, 16, in order to ensure that planetary gears (not shown)
or the like can be inserted into the later-manufactured carrier, the auxiliary openings
5 are punched on the front-end side of the wall 11 to a predetermined height and formed
into the openings 5. At the same time or almost simultaneously, the groove 4 designed
as a bending guide is formed on the border between the pre-flange (2) and the pre-joints
(3) on the inner periphery of the wall 11 either along the entire circumference or
discontinuously.
[0098] Then, as shown in Figs. 17, 18, the wall 11 is preliminarily closed off at an appropriate
angle from the groove 4 so that the front-end opening in the wall 11 (the outer peripheral
end face Wa of the material W) is slightly shrunk radially inwardly.
[0099] Thereafter, according to this embodiment, as shown in Figs. 19, 20, each of the closing-off
mandrels 12 is inserted from one of the openings 5 to another one adjacent thereto
so as to be close to a corresponding one of the joints 3, and pressed by a pressing
machine shown in Figs. 29, 30. The material W is then closed off so that the front-end
opening in the wall 11 (the cup-shaped opening defined by the outer peripheral end
face Wa of the material W) is shrunk radially inwardly, until the pre-flange (2) becomes
parallel to the flange 1.
[0100] A pressing machine for closing off the preliminarily closed-off material according
to an embodiment of the invention will be described. As shown in Figs. 29, 30, the
pressing machine has an upper mold 40 and a lower mold 41, which are vertically movable
relative to each other. The upper mold 40 has a punch 42, which presses the front-end
opening Wa of the preliminarily closed-off material W when the upper mold 40 is relatively
close to the lower mold 41. The lower mold 41 has a die 43 for accommodating the preliminarily
closed-off material W, an ejector 44 slidably fitted into the die 43 to support the
material W, and an ejector rod 45 for vertically moving the ejector 44 in the die
43. The inner diameter of the die 43 is approximately equal to the diameter of a bottom
of the cup-shaped material W, which is to be the flange 1. Although not shown, holes
are made in the die 43 so as to correspond to the openings 5 made between the joints
3 of the material W. The closing-off mandrels 12 can be inserted into the openings
5 in the material W through the holes (see Fig. 19). The height of the closing-off
mandrels 12 is approximately equal to the distance between the inner faces of the
flanges 1, 2 of the carrier C.
[0101] When the preliminarily closed-off material W is closed off, the material W is first
accommodated in the die 43 with the upper mold 40 and the lower mold 41 being spaced
apart from each other, and the closing-off mandrels 12 are inserted from the openings
5. In this state, if the upper mold 40 and the lower mold 41 are moved towards each
other, the punch 42 presses the front-end opening Wa of the preliminarily closed-off
material W as shown in Fig. 29. Thereby the preliminarily closed-off material W is
bent so that the front-end opening Wa of the material W is shrunk radially inwardly,
until the wall 11 extends substantially at a right angle from the groove 4, namely,
until the wall 11 becomes parallel to the flange 1. Thus, the portions among the openings
5 in the circumferential direction constitute the joints 3, and the portion (2) which
substantially forms a right angle with the joints 3 and which extends parallel to
the flange 1 constitutes the flange 2. That is, the foregoing processes are performed
to integrally form the joints 3 and the flange 2 so that they continue from the flange
1. The closed-off front-end opening (the outer peripheral end face Wa) constitutes
the through-hole 2a through which a shaft (not shown) or a sun gear (not shown) is
inserted. At this moment, especially the front-end opening Wa of the closed-off material
W generally tends to be crimpled because the material is compressed in the circumferential
direction by being shrunk. However, the material W is thick enough to demonstrate
rigidity for preventing especially the front-end opening Wa from being crimpled but
is thin enough to sufficiently save the weight of the carrier C. In addition, according
to the invention, since the pre-flange (2) of the wall 11 is pressed so as to be sandwiched
between the closing-off mandrels 12 and the punch 42 as shown in Fig. 30, the material
W is prevented from being crimpled. Because the auxiliary openings 5' and the openings
5 are made in advance before the material W is bent and drawn, the end faces of the
flanges 1, 2 facing the openings 5 are not curved so as to face each other. Because
the flanges 1, 2 and the joints 3 are integrally formed with uninterrupted flow of
the material W, the carrier C is formed with high rigidity. For this reason, the flanges
1, 2 and the joints 3 can be made relatively thin, whereby it becomes possible to
save the weight of the carrier C. After the material W has been closed off, the upper
mold 40 and the lower mold 41 are moved away from each other. The ejector 44 is then
raised with respect to the die 43 by driving the ejector rod 45, and the thus-formed
carrier C is fetched from the die 43.
[0102] Thereafter, as shown in Figs. 21, 22, auxiliary holes 7' are made in the flange 2
of the carrier C so as to correspond to the engagement holes 6 made in the flange
1. As is the case with the auxiliary holes 6' (see Figs. 7, 8) first made in the flange
1, the auxiliary holes 7' are set in a dimension slightly smaller than a dimension
allowing engagement with the rotational shafts of the planetary gears. As is the case
with the engagement holes 6 in the flange 1, as shown in Figs. 23, 24, after the auxiliary
holes 7' have been made, the material W is chamfered so that the peripheries of sides
of the auxiliary holes 7' which are to be the inside of the carrier C are inclined
with a diameter gradually increasing towards the inside of the carrier C.
[0103] The auxiliary holes 7' can be chamfered using a chamfering machine 20 as shown in
Fig. 24. The chamfering machine 20 has a master cam member 21 inserted into the carrier
C through one of the openings 5, an auxiliary cam member 22 longitudinally movably
supported in the master cam member 21, and a chamfering punch 23 protruded from the
master cam member 21 by the auxiliary cam member 22. One end face 21a of the master
cam member 21 is inclined in the shape of a cam so that the chamfering punch 23 moves
into the opening 5 and faces a corresponding one of the auxiliary holes 7' as a cam
24 moves vertically. The chamfering punch 23, which faces one of the engagement holes
7 to be chamfered, is retained at the other end of the master cam member 21 such that
the chamfering punch 23 can protrude therefrom. End faces 22a, 22b of the auxiliary
cam member 22 are inclined in the shape of a cam, and an insertion hole 21c is made
in the master cam member 21 at the end on the side of the cam-shaped end face 21a
so that a cam 25 can press the cam-shaped end face 22a of the auxiliary cam member
22. Furthermore, an end face 23a of the chamfering punch 23 located in the master
cam member is inclined in the shape of a cam so as to correspond to the inclination
of the end face 22b of the auxiliary cam member 22. The other end face 23b of the
chamfering punch 23 is formed so as to correspond to a shape into which the engagement
holes 7 are chamfered.
[0104] In the thus-constructed chamfering machine 20, the master cam member 21 is disposed
so as to correspond to one of the openings 5 between the joints 3. If the cam-shaped
end face 21a of the master cam member 21 is pressed by the cam 24 that is vertically
driven by a pressing machine (not shown), the chamfering punch 23 moves so as to match
a corresponding one of the unchamfered auxiliary holes 7' and the master cam member
21 is inserted into a space between the flanges 1, 2 through the opening 5 of the
joints 3. At this moment, the cam-shaped end face 22a of the auxiliary cam member
22 on the side of the insertion hole 21c is not being pressed by the cam 25. Accordingly,
the chamfering punch 23 is accommodated in the master cam member 21 without protruding
therefrom.
[0105] Thereafter, if the cam-shaped end face 22a of the auxiliary cam member 22 on the
side of the insertion hole 21a is pressed by the cam 25, the chamfering punch 23 protrudes
from the master cam member 21. After the auxiliary holes 7' have been made, the peripheries
of their sides which are to be the inside of the carrier C are inclined with a diameter
gradually increasing towards the inside of the carrier C and chamfered.
[0106] After completion of the aforementioned chamfering of the auxiliary holes 7', the
auxiliary holes 7' that have changed in dimension by being chamfered are finished
into the engagement holes 7 having a dimension allowing engagement with the rotational
shafts of the planetary gears, as shown in Figs. 25, 26.
[0107] Finally in the thus-formed carrier C, as shown in Figs. 27, 28, while the swaging
mandrels 13 are inserted through the openings 5 and disposed in positions which are
between the flanges 1, 2 and which are around the engagement holes 6, 7 for engagement
with the rotational shafts of the planetary gears, namely, positions which at least
serve to mount the rotating bodies, the flanges 1, 2 are coined towards the swaging
mandrels 13 by a press (not shown) or the like, as shown in Figs. 27, 28. Coining
means a process of finishing the flanges while pressing them by means of a press or
the like for the purpose of eliminating the surface roughness of the flanges. At the
same time, coining helps enhance the parallel precision of the flanges 1, 2. The swaging
mandrels 13 have parallel faces which are opposed to the flanges 1, 2. The width (height)
of the faces is set so as to substantially coincide with a desired distance between
the opposed faces of the flanges 1, 2 of the carrier C. Thus, according to the invention,
the flanges 1, 2 and the joints 3 are integrally formed and the opposed faces of the
flanges 1, 2 of the carrier C are swaged towards the swaging mandrels 13, whereby
it becomes possible to form the carrier C with high degrees of parallel precision
and dimensional precision.
[0108] In the thus-formed carrier C, planetary gears are inserted into a space between the
flanges 1, 2 from the openings 5, and the ends of rotational shafts of the planetary
gears engage the engagement holes 6, 7 made in the flanges 1, 2 respectively. The
planetary gears are rotatably and stably supported with their rotational shafts being
supported by both the flanges 1, 2 which demonstrate a high degree of parallel precision.
[0109] Methods of manufacturing a carrier according to other embodiments of the invention
will be described with reference to Figs. 31 through 38. The description of the following
embodiments will be focused on what is different from the aforementioned embodiment.
The components similar to or corresponding to those in the aforementioned embodiment
will be denoted by the same reference numerals, and the description of the components
or the detailed description and graphical representation of the components will be
omitted.
[0110] Fig. 31 shows a method of manufacturing the carrier C according to a second embodiment
of the invention. Fig. 32 shows a third embodiment of the invention. Fig. 33 shows
a fourth embodiment of the invention. Fig. 34 shows a fifth embodiment of the invention.
Fig. 35 shows a sixth embodiment of the invention. Fig. 36 shows a seventh embodiment
of the invention. Fig. 37 shows an eighth embodiment of the invention. Fig. 38 shows
a ninth embodiment of the invention.
[0111] In the second embodiment, as shown in Fig. 31A, one of the through-holes la, through
which a shaft (not shown) or a sun gear (not shown) is inserted, is first of all made
at the center in one of pre-flanges (1) of the plate material W formed into a circular
shape, and the plate material W is bent and drawn into the shape of a cup. Thereafter,
as shown in Fig. 31B, the opening 5 is made in a lower portion (of the drawing) in
the wall 11 of the cup-shaped material W. The groove 4 designed as a bending guide
is formed in the inner periphery of the wall 11 of the material W on the border between
the joint 3 and the other flange 2. Then, as shown in Fig. 31C, the outer peripheral
portion of the flange 1 which faces the opening 5 is flattened. As shown in Fig. 31D,
the material W is preliminarily closed off at an appropriate angle from the groove
4 so that the front-end opening of the wall (the outer peripheral end face Wa of the
material W) is slightly shrunk radially inwardly by means of spinning or the like.
Thereafter, as described above (see Figs. 19, 20), the closing-off mandrels 12 are
inserted from the openings 5 and the material W is pressed. The material W is then
closed off so that the front-end opening in the wall 11 (the outer peripheral face
Wa of the material W) is shrunk radially inwardly, until the pre-flange (2) becomes
parallel to the flange 1. Thus, the integral-type carrier C is formed so that the
joints 3 for connecting the opposed flanges 1, 2 continue therefrom.
[0112] In the third embodiment, as is the case with the second embodiment, as shown in Fig.
32A, one of the through-holes la, through which a shaft (not shown) or a sun gear
(not shown) is inserted, is first of all made at the center in one of pre-flanges
(1) of the plate material W formed into a circular shape, and the plate material W
is bent and drawn into the shape of a cup. Thereafter, as shown in Fig. 32B, the groove
4 designed as a bending guide is formed in the inner periphery of the wall 11 of the
cup-shaped material W in a portion which is to be the border between the joints 3
and the flange 2. Then, as shown in Fig. 32C, the material W is preliminarily closed
off at an appropriate angle from the groove 4 so that the front-end opening in the
wall 11 is slightly shrunk radially inwardly by means of spinning or the like. Then,
as shown in Fig. 32D, the material W is closed off so that the front-end opening in
the wall 11 (the outer peripheral face Wa of the material W) is shrunk radially inwardly,
and the integral-type carrier C is formed so that the joints 3 for connecting the
opposed flanges 1, 2 continue therefrom. The openings 5 are thereafter made in the
joints 3 (not shown).
[0113] In the fourth embodiment, as shown in Fig. 33A, one of the through-holes la, through
which a shaft (not shown) or a sun gear (not shown) is inserted, is first of all made
at the center in one of pre-flanges (1) of the plate material W formed into the shape
of a disc, and the openings 5 are made around the through-hole la. Thereafter, the
plate material W is bent and drawn into the shape of a cup as shown in Fig. 33B, and
the groove 4 designed as a bending guide is formed in the inner periphery of the wall
11 of the cup-shaped material W in a portion which is to be the border between the
joints 3 and the flange 2. Then, as shown in Fig. 33D, the material W is preliminarily
closed off at an appropriate angle from the groove 4 so that the front-end opening
in the wall 11 is slightly shrunk radially inwardly by means of spinning or the like,
and the material W is then closed off so that the front-end opening in the wall 11
(the outer peripheral end face Wa of the material W) is shrunk radially inwardly.
Thus, the carrier C is integrally formed so that the joints 3 for connecting the opposed
flanges 1, 2 continue therefrom, as in the aforementioned embodiments.
[0114] Then in the fifth embodiment, as is the case with the fourth embodiment, as shown
in Fig. 34A, one of the through-holes la, through which a shaft (not shown) or a sun
gear (not shown) is inserted, is first of all made at the center in one of pre-flanges
(1) of the plate material W formed into the shape of a disc, and the openings 5 are
made around the through-hole la. Then, as shown in Fig. 34B, the groove 4 designed
as a bending guide is formed in the inner periphery of the wall 11 of the plate material
W in a portion which is to be the border between the joints 3 and the flange 2. Then,
as shown in Fig. 34C, the plate material W is bent from the groove 4 and drawn into
the shape of a cup. That is, as long as the bending guide 4 of the invention is formed
before the material W is closed off, the bending guide 4 may be formed before the
plate material W is bent and drawn into the shape of a cup. In this embodiment, the
wall 11 formed by bending and drawing the material W constitutes only the flange 2.
Thereafter, as shown in Fig. 34D, while the border between the pre-flange (1) and
the pre-joints (3) is being bent, the material W is closed off so that the front-end
opening in the wall 11 (the outer peripheral end face Wa of the material W) is shrunk
radially inwardly. Thereby the integral-type carrier C is formed so that the joints
3 for connecting the opposed flanges 1, 2 continue therefrom.
[0115] Unlike the aforementioned embodiments, a tubular material W is prepared in the sixth
embodiment. In this embodiment, as shown in Fig. 35A, the openings 5 are first of
all made at the axial centers in the tubular material W. Thereafter, the tubular material
W is formed into the shape of a cup by closing off one end thereof as shown in Fig.
35B. Furthermore, as shown in Fig. 35C, the other end Wa of the material W, which
is a cup-shaped opening, is closed off, whereby the opposed flanges 1, 2 and the joints
for connecting them are integrally formed. Before both the ends of the tubular material
W are sequentially closed off, they are preliminarily closed off as described above.
The openings 5 may not necessarily be made at the outset. Namely, the openings 5 may
also be made after one or the other end of the tubular material W has been closed
off. Although not shown in this embodiment, a groove designed as a bending guide is
formed in the inner periphery of the material W in a portion which is to be the border
between the joints 3 and the flange 2. The groove may also be formed in the inner
periphery of the tubular material W in a portion which is to be the border between
the flange 1 and the joints 3 before the material W is formed into the shape of a
cup by closing off one end thereof to form the flange 1. As described above, the auxiliary
holes 6', 7', which are to be the engagement holes 6, 7 for engagement with rotational
shafts of planetary gears, may be made in advance in the tubular material W.
[0116] In the seventh embodiment, as is the case with the aforementioned sixth embodiment,
the tubular material W with the openings 5 made in its axial centers is prepared as
shown in Fig. 36A. The seventh embodiment is different from the sixth embodiment in
that both the ends Wa of the tubular material W are closed off simultaneously. That
is, as shown in Fig. 36B, both the ends Wa of the tubular material W are preliminarily
closed off at the same time. Furthermore, as shown in Fig. 36C, both the ends Wa are
closed off simultaneously, whereby the opposed flanges 1, 2 are formed. The axial
centers of the tubular material W, which are not closed off, constitute the joints
3 for integrally connecting the flanges 1, 2.
[0117] Unlike the aforementioned embodiment, in the eighth embodiment, a rod material W
is prepared as shown in Fig. 37A. "The rod material" means a material which has a
predetermined length (predetermined thickness) L in the axial direction of the carrier
so as to be formed into the shape of a cup by backward extrusion or the like and which
is thicker than the aforementioned plate material. In this embodiment, as shown in
Fig. 37B, the rod material W is first of all formed into the shape of a cup by backward
extrusion or the like. Thereafter, as shown in Fig. 37C, one of the through-holes
la, through which a shaft (not shown) or a sun gear (not shown) is inserted, is made
in the bottom of the cup-shaped material W. The cup-shaped opening Wa is then closed
off, whereby the opposed flanges 1, 2 and the joints 3 for connecting them are integrally
formed as shown in Fig. 37D. The openings 5 among the joints 3 and the like can be
made after the rod material W has been formed into the shape of a cup.
[0118] In the ninth embodiment, unlike all the aforementioned embodiments wherein the flange
2 or both the flanges 1, 2 are formed by closing off the material W, the joints 3
are formed by bulging the axial centers of the tubular material W radially outwardly,
and accordingly, the flanges 1, 2 are integrally formed so as to be opposed to each
other and extend from the joints 3 radially inwardly. Fig. 38 shows a mechanical bulging
machine for bulging the tubular material. In Fig. 38, while the material has not been
bulged on the left side with respect to a center line indicated by a chain line, the
material has been bulged on the right side with respect to the center line.
[0119] The bulging machine according to one embodiment of the invention will be described
with reference to Fig. 38. This bulging machine has an upper mold 50 and a lower mold
51 which are vertically movable relative to each other, punches 52 for pressing the
tubular material W so as to bulge its axial centers, and a cam mechanism 53 for driving
the punches 52 radially outwardly. In this embodiment, the upper mold 50 is supported
by a vertical-drive rod 54 so that the upper mold 50 vertically moves relative to
the lower mold 51. Receptacles 50a, 51a for receiving the tubular material W and cavities
50b, 51b for determining the configuration of the bulged material are formed in a
butt face which is formed when the upper mold 50 and the lower mold 51 are closed.
The punches 52 are divided in the radial direction of the material W and radially
slidably supported by punch plates 55 disposed inwardly of the receptacle 50a of the
upper mold 50. A punch holder 56 is disposed below the punches 52. A receptacle 57,
which receives the punch holder 56 when the upper mold 50 and the lower mold 51 are
butted against each other, is formed inwardly of the receptacle 51a of the lower mold
51. A stopper 52a protrudes from a radially intermediate position on the lower surface
of each of the punches 52. Stoppers 56a, 56b are formed at radially inner and outer
positions on the upper surface of the punch holder 56. A spring 58 is interposed between
the stopper 52a of each of the punches 52 and the radially outer stopper 56a of the
punch holder 56 so as to urge each of the punches 52 to retract radially inwardly.
The cam mechanism 53 drives each of the punches 52 radially outwardly against the
urging force of the spring 58 and is composed of a cam face 52b formed radially inwardly
of each of the punches 52 and a cam member 59 bonded to the cam face 52b. The upper
end of the cam member 59 is connected to a drive plate 60. The vertical-drive rod
54 is inserted through the drive plate 60 so as to vertically drive the drive plate
60 relative to the upper mold 50.
[0120] In the thus-constructed bulging machine, if the drive plate 60 is moved downwards
with respect to the upper mold 50 from the state shown on the left side of Fig. 38,
the axial centers of the tubular material W are pressed outwardly by the cam member
52 and bulged so as to follow the cavities 50b, 51b of the upper and lower molds 50,
51. Thus the joints 3 are formed. At the same time, both the axial ends of the tubular
material W constitute a pair of the opposed flanges 1, 2. The through-holes la, 2a,
through which shafts (not shown) and sun gears (not shown) are inserted, are defined
by both the end faces Wa of the tubular material W. As can be seen from Fig. 35A and
Fig. 36A, the holes 5', which are to be the openings 5, are made in advance in the
axial centers of the tubular material W. In consideration of the fact that the holes
5' are enlarged radially and axially when the material W is bulged, the dimension
of the holes 5' is set in accordance with the dimension of the openings 5. After the
material W has been bulged, the drive plate 60 is moved upwards with respect to the
upper mold 50, whereby the radial end of each of the punches 52 is displaced to a
position inwardly of the through-hole 2a due to the urging force of the spring 58.
Therefore, each of the punches 52 can move away from the carrier C through the through-hole
2a as the upper mold 50 ascends.
[0121] The invention is not limited to the aforementioned embodiments. It is possible to
employ a hydraulic bulging machine (not shown) instead of the mechanical one. In this
case, a working fluid is supplied into a tubular material at a predetermined pressure.
Therefore, the tubular material is sealed to prevent the working fluid from leaking
out from the holes which are made in advance in the axial centers of the tubular material
and which are to be the openings 5. Alternatively, the holes which are to be the openings
5 are not made in advance in the tubular material, and the openings 5 are made in
the material after it has been bulged.
1. A carrier
characterized by comprising:
a pair of flanges (1, 2) opposed to each other and designed to rotatably support rotating
bodies between the flanges (1, 2);
joints (3) that connects the flanges (1, 2), wherein:
the flanges (1, 2) and the joints (3) are integrally formed through plastic deformation
of a single material.
2. The carrier according to claim 1, characterized in that:
the joints (3) are disposed along outer peripheries of the flanges (1, 2).
3. The carrier according to claim 2, characterized in that:
openings (5) are made in the joints (3).
4. The carrier according to any one of claims 1 to 3,
characterized in that:
a groove (4) is formed on a border between the flanges (1, 2) and the joints (3).
5. The carrier according to any one of claims 1 to 3,
characterized in that:
through-holes (1a, 2a) opposed to each other and designed to penetrate the flanges
(1, 2) are made on the inner circumferential side of the flanges (1, 2).
6. The carrier according to any one of claims 1 to 3,
characterized in that:
engagement holes (6, 7) for engagement with rotational shafts for rotatably supporting
rotating bodies in the carrier are made in the flanges (1, 2).
7. A method of manufacturing a carrier having a pair of flanges (1, 2) and rotatably
supporting rotating bodies between the flanges (1, 2),
characterized by comprising the steps of:
forming a material into the shape of a cup having an opening; and
closing off the opening of the cup so that a pair of flanges (1, 2) opposed to each
other and designed to rotatably support rotating bodies between the flanges (1, 2)
and joints (3) for connecting the flanges (1, 2) are integrally formed.
8. The method according to claim 7, characterized in that:
the material is selected from a plate material, a rod material and a tubular material.
9. A method of manufacturing a carrier having a pair of flanges (1, 2) and rotatably
supporting rotating bodies between the flanges (1, 2),
characterized by comprising the steps of:
preparing a tubular material;
closing off both end openings of the tubular material so that a pair of flanges (1,
2) opposed to each other and designed to rotatably support rotating bodies between
the flanges (1, 2) and joints (3) for connecting the flanges (1, 2) are integrally
formed.
10. The method according to claims 7 or 9, characterized in that:
a bending guide (4) is formed on a border between pre-joints (3) and pre-flanges
(1, 2) before the material is closed off.
11. The method according to claim 10, characterized in that:
a groove is formed as the bending guide (4) on a side of the border to which the
flanges (1, 2) are opposed.
12. The method according to claims 7 or 9, characterized in that:
openings (5) are made in pre-joints (3) of the material before the material is
closed off.
13. The method according to claim 12, characterized in that:
mandrels are inserted from the openings (5) made in the pre-joints (3) of the material
so as to close off the material.
14. The method according to claims 7 or 9, characterized in that:
engagement holes (6, 7) for engagement with rotational shafts for rotatably supporting
rotating bodies in the carrier are made in pre-flanges (1, 2) before the material
is closed off.
15. The method according to claim 14, characterized in that:
mandrels are interposed in positions for mounting rotating bodies between the flanges
(1, 2) so that the flanges (1, 2) are swaged towards the mandrels (13).
16. The method according to claims 7 or 9, characterized in that:
openings (5) are made in the joints (3) of the material after the material has
been closed off.
17. The method according to claim 7,
characterized in that:
the material is selected from a plate material and a tubular material; and
openings (5) are made in the pre-joints of the material before the material is formed
into the shape of a cup.
18. The method according to claim 7,
characterized in that:
the material is selected from a plate material and a tubular material; and
a bending guide (4) is formed on a border between pre-joints (3) and a pre-flange
(1, 2) of the material before the material is formed into the shape of a cup.
19. The method according to claim 18, characterized in that:
a groove is formed as the bending guide (4) on a side of the border to which the
flanges (1, 2) are opposed.
20. The method according to claim 7,
characterized in that:
a bottom of the material formed into the shape of the cup is turned into a first flange
(1);
peripheral walls adjacent to the bottom are turned into joints (3); and
an opening-side portion of the cup-shaped material, which is to be closed off, is
turned into a second flange (2).
21. The method according to claim 9,
characterized in that:
axial centers of a side wall of the tubular material are turned into the joints (3);
and
both axial ends of the side wall of the tubular material, which are to be closed off,
are turned into a pair of flanges (1, 2).
22. A method of manufacturing a carrier having a pair of flanges (1, 2) and rotatably
supporting rotating bodies between the flanges (1, 2),
characterized by comprising the steps of:
preparing a tubular material having a tubular wall surface;
bulging a wall surface at the axial center of the tubular material radially outwardly
so that a pair of flanges (1, 2) opposed to each other and designed to rotatably support
rotating bodies between the flanges (1, 2) and joints (3) for connecting the flanges
(1, 2) are integrally formed.
23. The method according to claim 22, characterized in that:
openings (5) are made in pre-joints (3) of the material before the material is
closed off.
24. The method according to claim 22, characterized in that:
engagement holes (6, 7) for engagement with rotational shafts for rotatably supporting
rotating bodies in the carrier are made in pre-flanges (1, 2) before the material
is closed off.
25. The method according to claim 22, characterized in that:
mandrels (12) are interposed in positions for mounting rotating bodies between
the flanges (1, 2) so that the flanges (1, 2) are swaged towards the mandrels (12).
26. The method according to claim 22,
characterized in that:
axial centers of the bulged side wall are turned into the joints (12); and
both axial ends of the side wall of the tubular material, which are to be closed off,
are turned into a pair of flanges (1, 2).